The MIMO technology has become one of the key technologies of the next generation wireless communication system. Currently, the research on a point-to-point single-user MIMO system has been becoming mature. However, in the practical application, the system usually needs a base station (BS) that can communicate with a plurality of user equipments (UE) simultaneously. Therefore, the research on a point-to-multipoint Multi-user MIMO system has increasingly become the focus.
The Multi-user MIMO system is more complicated than the single-user AMMO system. Considering the fact that the application of the actual communication network will raise various questions in respect of scheduling and noise reduction, the algorithm with high complexity and high computing cost will be involved.
Taking scheduling of users in the Multi-user MIMO system as an example, the scheduling of users in the Multi-user MIMO system may be divided into a selective user scheduling algorithm and a non-selective user scheduling algorithm. Exhaust algorithm and greedy search algorithm in the selective user scheduling algorithm have better performance, but at a cost of high complexity. When the number of antennas or users is large, the problem that the scheduling of users cannot be completed in time or the cost of computing devices is high may be caused due to its high complexity. The non-selective user scheduling algorithm such as a Round-Robin scheduling algorithm and a random scheduling algorithm may result in bad performance of the scheduling, thus fail to meet the system requirement.